This work began with the Usability Problem Taxonomy [Keenan, 1996; Keenan, Hartson, Kafura, & Schulman, 1999] and the Usability Problem Classifier [van Rens, 1997]. As our work expanded to include other tools, we sought a unifying model, which we found in Norman's stages-of-action model [Norman, 1986], a theory-based model that highlights issues about the way people interact with any kind of machine, independent of interaction style or devices. Thus, the UAF is structured by what we call the Interaction Cycle, an adaptation and extension of Norman's stages of action model of user interaction [Norman, D. A. (1986). Cognitive Engineering. In D. A. Norman & S. W. Draper (Ed.), User Centered System Design. Hillsdale, NJ: Erlbaum, 31-61].
Built upon the Interaction Cycle, the User Action Framework is now a structured knowledge base organized as a search or classification space of usability concepts, issues, and situations. The UAF provides a unifying structure on which we are building a suite of tools to support usability inspection, design guidelines, classification and reporting of usability problems, and usability problem databases. Through the Interaction Cycle, the framework is structured on the simple idea of how the user is affected by the design during interaction at various points where the user must make cognitive or physical actions.
The User Action Framework built as a usability concepts knowledge base upon the Interaction Cycle
The importance of reliability in the User Action Framework
Terminology in the User Action Framework
The UAF-based usability engineering support tools
Follow this link to see an on-line version of the UAF: UAF version for public viewing . Read this page and then click on the "Explorer" tab.
UAF Training tool